The example of the judge is an instructive one, although a little extreme. Due to the immense power vested in judges, even the tiniest perception of bias must be avoided.
For instance, we might find it a bit troubling if the judge in a case is golfing with one of the lawyers on the weekend while the trial is ongoing, even if no gift or consideration is involved. Judges must also take care not to comment publicly on politics and thereby threaten their independence from the executive and legislative branches of government.
In contrast, in the Winnipeg city council example the gift is from the mayor to council members - all of them. They are all elected officials, including the gift-giver, and they work together on a daily basis. In fact, they might in the normal course of their jobs declare open allegiance or opposition to the positions of another member. Unlike a judge, who is sworn to impartiality and must exercise her judgement solely based on the facts before her, politicians are elected by the public based on their express declaration of partiality to a particular set of viewpoints. If we learned that the Mayor golfs with certain city council members who are known to oppose his policies, we might commend him for reaching across the aisle and fostering dialogue.
So while elected officials must be free from bribery, I don't think it's appropriate to apply the same standard with respect to token gifts that we would apply to a judge who acts as a finder of fact within an adversarial system.